Build Your Own Clone Message Board

Hi there!

The blend knob on my Mimosa Jr. doesn't seem to be working properly... when turned fully counter clockwise there is no signal. Turning it up appears to increase the compressed signal level, but there doesn't appear to be any dry signal. The volume knob seems to work normally when the blend is at any position besides fully CCW.

I tried reflowing my solder joints, but no effect.

- The bypass is working
- The LED is on
- When the pedal is on, and the Blend is anywhere but fully CCW, there is a compressed tone happening... Volume controls master volume, blend controls level of compressed signal only.

Thanks in advance.

You've probably got a cold solder joint or a short somewhere in the dry signal path. Because the wet path is working, we can assume all the semi-conductors are working just fine. Try reflowing your solder joints. Keep an eye out for any solder blobs that look like they might be touching something they shouldn't.

If you have a signal tester, you can track down the problem pretty easily.

_________________
*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com

Here are the Mimosa Jr. schematic and PCB map, if you wish to trace out the dry signal path, which is the upper section between pin 7 of IC1b and the blend pot. There's a higher resolution schematic in PDF format here: http://byocelectronics.com/mimosajrschematic.pdf

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

Update: I think I fixed it! I had accidentally cut/scorched the trace between Pin 9 and the 100k/33k resistor bridge... I used a leg of a resistor to join all 3 of these together. I had noticed my IC pin 8 was reading 9v instead of the 4.5v.

Seems to be working now. Unity gain with blend at 0 is a little past noon, more like 2-3 o clock. but sounds great!

Good job chasing that down! Looking at the back of your PCB in that area around the IC, I can see what you're talking about. Looks pretty rough around pins 9 & 10 and the joints for those two resistors.

Enjoy the new pedal!

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

Thank you! Yeah... I went a little too hogwild trying to fix a solder bridge between those two resistors... only to realize from the schematic later they were meant to be linked

This is my second BYOC kit and I've really enjoyed the learning process making both!

Practice makes perfect!

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2